Natural gas is one of the most economical and convenient means by which hydrocarbon energy can be used for commercial and domestic heating. It is also used as a fuel for internal combustion engines. The gas must be conveyed by pipelines and it is customary to bury the pipelines adjacent roadways and alleyways. The supply line is connected to a lateral by a gas meter. The lateral is connected to a home or a gas engine and the gas meter measures the quantity of gas consumed so that the utility company can be compensated for the quantity of gas that flows from the main supply line.
A riser usually is connected to the main supply line and extends above the ground level to a gas valve which controls the flow of gas to the gas meter. Occasionally, for one reason or another, a negligent vehicle operator will run into the gas meter and this usually breaks one of the pipes that makes up the riser leading from the underground supply pipe to the gas meter. The riser usually breaks at the threaded pipe connection between the supply pipe and the valve. When this happens, it is impossible for the layman to shut off the flow of gas because the valve is located downstream of the broken pipe. Accordingly, gas escapes from the riser and into the atmosphere until an expert from the utility company arrives to shut off the gas flow. The escape of gas into the atmosphere brings about a costly and dangerous situation.
It would therefore be desirable to be able to provide a gas flow measuring system having a gas meter positioned above the ground and connected to a gas supply pipe by piping that includes a special valve device therein that always causes the piping to break at a location downstream of the valve rather than upstream of the valve. By selecting the location in the piping system where the break will usually occur provides a means by which anyone can turn the existing valve to the off position and thereby obviate the waste of the gas and the danger of explosion.
Apparatus that achieves the above desirable attributes is the subject of the present invention.